Apparatus for treatment of granulated foods

ABSTRACT

An apparatus for treating granular material, such as plastic granulate or the like, developed as a circulation drier acting on the treatment material with high air temperature and brief time of heating in the manner of a heat shock, comprising a funnelshaped storage container in which the material treated is contained having an upper filling opening and a lower outlet portion having a lower outlet opening, and a T-member having horizontal disposed branches and a vertical connection branch, the lower outlet portion of the container being operatively connected to the vertical connection branch for discharge of the material from the container, into the T-member. A pressure air blower is operatively connected to a line being connected downstream to one of the horizontal disposed branches of the Tmember. An automatically controlled heating device is operatively interposed between the air blower and the one end of the horizontal disposed branch of the T-member, and a conveyor line is connected to the other horizontal disposed branch of the Tmember and operatively to the lower outlet portion of the storage container. The conveyor line is connected downstream to an annular channel of approximately U-shaped cross section with the opening of the U towards the bottom, and constituting an air separator, the annular channel extending concentrically around the upper filling opening in the inside of the storage funnel. An outlet valve is disposed in the center of the lower outlet opening in the storage container and controllable from the outside and extends in a vertical direction downwardly and outwardly through the horizontal branch portion of the T-member, and, an air guide web is substantially disposed in a plane in the front portion of the T-member, and a common heat storage insulated housing is provided.

United States Patent Stuhlmann et al.

[451 July 25, 1972 [54] APPARATUS FOR TREATMENT OF GRANULATED FOODS [72] Inventors: Hans Stuhlmann, Dusseldorf; Werner Stuhlmann, Wuppertal-Elberfeld, both of Germany Firma Battenfeld Maschlnenfabriken Gmbll, Meinerzhagen, Germany 22 Filed: March 8,1971

21 Appl.No.: 121,988

[73] Assignee:

[30] Foreign Application Priority Data March 10, 1970 Germany ..P 20 11 278.1

['52] US. Cl. ..34/48, 34/57 R [51] Int. Cl ..F26b 19/00 [58] Field ofSearch ...34/l0, 44, 48, 57 R,57E

Primary Examiner-Carroll B. Dority, Jr. Attorney- Ernest G. Montague 57 1 ABSTRACT An apparatus for treating granular material, such as plastic granulate or the like, developed as a circulation drier acting on the treatment material with high air temperature and brief time of heating in the manner of a heat shock, comprising a funnel-shaped storage container in which the material treated is contained having an upper filling opening and a lower outlet portion having a lower outlet opening, and a T-member having horizontal disposed branches and a vertical connection branch, the lower outlet portion of the container being operatively connected to the vertical connection branch for discharge of the material from the container, into the T- member. A pressure air blower is operatively connected to a line being connected downstream to one of the horizontal disposed branches of the T-member. An automatically controlled heating device is operatively interposed between the air blower and the one end of the horizontal disposed branch of the T-member, and a conveyor line is connected to the other horizontal disposed branch of the T-member and operatively to the lower outlet portion of the storage container. The conveyor line is connected downstream to an annular channel of approximately U-shaped cross section with the opening of the U towards the bottom, and constituting an air separator, the annular channel extending concentrically around the upper filling opening in the inside of the storage funnel. An outlet valve is disposed in the center of the lower outlet opening in the storage container and controllable from the outside and extends in a vertical direction downwardly and outwardly through the horizontal branch portion of the T-member, and, an air guide web is substantially disposed in a plane in the front po ;ion of the T-member, and a common heat storage insulated housing is provided.

6 Claims, 4 Drawing Figures PlTi'N'TEnJuLas I972 sum 1 0P3 INVENTORC BY: lmx )L APPARATUS FOR TREATMENT OF GRANULATED FOODS The present invention relates to an apparatus for the treating of granular material, such as plastic granulate or the like, in which the material to be treated is received in a funnelshaped storage container provided with an upper filling opening, the lower opening of which terminates in the vertical pipe branch of a T-piece, a conduit provided with an air blower being connected to one of the horizontal connections of the T.

An apparatus of the aforementioned type is known, for instance, as disclosed in British Patent No. 940,468. In this apparatus a T-piece is also arranged at the lower outlet end of a funnel-shaped container the connection of which is located in the vertical plane being connected with the outlet end of the funnel, while a conduit provided with an air blower is connected to one of the horizontal ends of the T-piece. This apparatus is a suction blower device for the separating of powdered milk.

Starting now from the principle of such an apparatus, the object of the present invention is to improve same so that it is suitable for the drying of plastic granulate and so that it has an extremely high efficiency with an extremely simple operation.

The object of the present invention is obtained first of all in an advantageous manner substantially by the fact that the apparatus is developed as a circulatory drier acting on the treatment material with high air temperature and brief heating in the manner of a heat shock, whereby, on the one hand, between the air blower which is developed as a pressure blower and connected to one of the horizontal connections of the T'piece and the T-piece itself, there is interposed a selfcontrolled heating device, while, on the other hand, there is connected to the other end of the T-piece a conveying conduit connecting the outlet of the storage hopper with an annular channel which extends concentrically around the upper filling opening within the storage hopper, approximately U-shaped in cross-section, with the opening of the U towards the bottom, and acts as an air separator, and that furthermorein the center of the outlet opening on the hopper side there is provided an externally controllable outlet valve which extends through the horizontal connection of the T-piece vertically downwardly and outwardly and that in the same plane in front of it there is provided in the T-piece an air guide web which makes possible an eddy-free flow of dry air and that finally a storage container, heating device and pressure blower are suitably arranged in a common insulated housing which forms a heat storage device.

A practical embodiment of the present invention constitutes, as viewed from the standpoint of its construction, a simple solution which is excellently suitable in practice if only smallerquantities of plastic granulate have to be dried, as is true, for instance, for laboratory purposes or the like. The decisive advantage of the new apparatus is viewed in the fact that a continuous circuit for the material to be dried is produced which requires no observation whatsoever and can be left completely unsupervised. When the desired degree of dryness of the material being treated has been reached, it is merely necessary by a simple manual operation to open the outlet valve so thatthe dried material can flow out.

It is another object of the invention, to control the temperature of the treated material in the storage hopper and the temperature of theheating air in the heating deviceindependently of each other so that an optimum degree of drying can be obtained.

Another advantage of the apparatus in accordance with the present invention resides furthermore in the fact that the storage container for the receiving of the material to be dried, the heating device and the :pressure blower, are arranged in a common housingso that the entire apparatus forms a type of heat storage device, so that only brief starting-up times are necessary and .hot air is practically always available for the drying, while the cooling of the systemis not affected from the outside.

In this connection it is purposeful for the heating device to be arranged parallel to and alongside the storage hopper and for its upper-inletopening for the flowing air to be connected by an elbow acting as air cushion with an air feed line which extends laterally in a vertical plane alongside the heating apparatus.

By such an arrangement of the heating apparatus on the one hand with the characteristic feeding of the air to be heated via an elbow which is connected to the head of the heating device, the result is obtained namely that a heat cushion is formed in the elbow when the blower is disconnected so that the hot air cannot escape towards the compressed air blower side and furthermore no moisture can flow in from there.

By this heat-cushion effect on the one hand and by the entire design of the apparatus in a housing developed as heat storage device on the other hand, the apparatus can be considered particularly favorable from the standpoint of operation and efficiency since long starting-up times do not result since accumulated heat is practically always present in the apparatus itself.

Furthermore, this new apparatus results in further advantages from the construction standpoint insofar as an eddyfree flow of hot air is obtained in the manner that within the T- piece in the transition region between the outlet on the storage hopper side and the horizontally extending hot air feed line coming from the heating device there is provided an air guide web passing through the hot air feed conduit transversely to the longitudinal axis both over parts of its height and over parts of its width, leaving lateral air passage slots, which is concavely arched in the direction of flow of the air in the radius of the outlet connection on the storage hopper side and represents a bottom extension of said connection.

In this way one can operate without disturbance since the hot air flows past the air guide web in the direction of the longitudinal axis of the horizontal connection of the Tpiece so that an eddying of the material being treated within the storage container is prevented from its outlet opening.

Furthermore, a disturbance-free dependable operation in the sense of the circulation of the granulate to be dried is promoted if the outlet connection on the storage hopper side extends over a part of its height into the inside cross section of the hot air feed line arranged in the horizontal plane in such a manner that the outlet end of the outlet connection lies approximately midway of the cross-sectional height of the hot air feed line in the region of the T-piece.

By this measure there is formed within the hot air feed line by the granulate flowing down from the storage hopper a conical pile which never fills up the entire cross section of the cross-sectional heightof the hot air feed line so that no plug of granulate can be formed which might lead to clogging. The flowing hot air can in all cases always be active in the sense of carrying along granulate and due to the preventingof the formation of a plug of granulate, can also not be impeded, which is of decisive importance for a disturbancefree course of the circulation.

Finally it is also of importance for the simplicity of the construction that the outlet valve on the storage hopper side is developed as a ball valve, the valve ballof which isseated on an actuating rod which is extended to the outside and cooperates within the outlet opening with an inlet end of a valve tube which is seated concentrically in theoutletend.

By this measure there is developed an outlet valve of extremely simple design which on the one hand is of excellent sealing action and does not require any special maintenance and furthermore can be operated with extremely simple means even in case of the removal of small and very small quantities.

lnsummary, it has thus been possible by the present invention to provide a .drying device with recycle effect which is simple from a construction standpoint and yet is of extremely advantageous development and by its characteristic construction of combining all parts in a common insulated housing having air inlets on the one hand and by the feeding of air via an elbow discharging on the top of the heating device on the other hand to prevent disturbing cold air or the influence of moisture definitely affecting the drying process and thus excessively lengthening it. In this connection it is also advisable for the filling opening of the storage container to be closed by a filter cover.

By the circulatory drying proposed in accordance with the present invention, practically each individual particle of granulate is briefly heated and dried continuously while freely suspended in the hot stream of air. One can operate with air temperatures which are twice as high as those otherwise employed, which, of course, results in a much faster and more intensive drying of the granulates and is also more uniform due to the continuous nature of the operation, without any baking or sticking together occurring. This naturally has a very decisive effect on the further processing of the material and the quality of the plastic products produced from this granulate. If only for this reason, this drying apparatus must be considered an outstanding solution which has an extremely high efficiency.

With these and other objects in view which will become apparent in the following detailed description, the present invention will be clearly understood in connection with the accompanying drawings, in which:

FIG. 1 is a schematic elevation showing in overall view an apparatus in accordance with the present invention;

FIG. 2 is a fragmentary top plan view of the region of the air guide web in the T-piece;

FIG. 3 is a several times enlarged fragmentary axial section of the outlet in the region T-piece; and

FIG. 4 is another fragmentary axial section, turned 90 as compared with FIG. 3.

Referring now to the drawings, in this connection, first of all, a funnel-shaped storage container 10 has a filling opening 11 at its upper end and an outlet opening 12 at its bottom. The filling opening 11 can be closed by a filter cover 13. The lower end of the storage funnel 10 terminated in a connection 14 which is coupled to a T-piece 15, 16 formed ofa vertical connection l and a horizontal 16. To one end of this T-piece 15, 16 a hot air feed line 17 is connected, while a conveying line 18 for the material to be treated G is connected to the other end of the T-piece. This conveying line 18 connects the outlet 12 of the funnel with an annular channel 19 developed as an air separator and discharging tangentially into it. The annular channel 19 is located within the funnel concentrically around the filling opening 11 of the funnel which is open towards the bottom.

The air fed into the air feed line 17 comes from a compressed air generator 20 and is led via a connecting line 21 to a heating device 23. This heating device 23 is coupled via an elbow 24 which connects the top inlet opening 25 with the connecting line 21. The heating device 23 and the funnel 10 are each equipped in the region of the treatment material G with a separate thermostate 26 and 27, respectively, which operate independently of each other. The thermostate 26 maintains the temperature in the heating device 23 even when the blower 23 is not operating, while the thermostate 27 monitors the temperature of the granulate and when the value set is reached, disconnects the blower 20 or places it in operation again upon a decrease in the temperature. in addition, a safety thermostate 28 can, however, also be provided.

In the present embodiment, all functional components are located alongside of each other and are enclosed by a common housing 29 developed as an insulating housing. The funnel 10 or storage container is preferably located in the region between the pressure blower 20 and the heating device 23.

In the T-piece 15, 16 there is located, as extension of the connection 14, an air guide web 30 which passes in a vertical plane through the horizontal pipe connections 16 over parts of its height and width and leaves air passage slots 31 between its side edges and the inside of the connection, This air guide web 30 has a concave curvature in the direction of flow of the hot air corresponding to the radius of curvature of the connection 14. The mouth of the outlet connection 14 extends over a part of its height into the inside cross section of the hot air feed line 17 so that a conical heap 35 of granulate can never plug the entire cross section.

In the outlet 12 of the funnel 10 there is an outlet valve which comprises on the one hand a valve tube 32 and on the other hand a valve ball 33 at the end of an actuating rod 34. This valve tube is seated concentrically around the longitudinal center axis of the outlet 12 and leaves between its outer surface and the inner surface of the connection 14 an annular outlet opening through which the material G to be dried passes into the horizontal connection 16 of the T-piece 15, 16. The structural development of the outlet valve makes it possible, with very simple manipulation, to remove small or even very small quantities from the storage funnel 10 which always contains a supply ready for processing.

The manner of operation of this apparatus is best understood as follows.

The treatment material 6" passes through the annular outlet 12 at the bottom end of the funnel into the horizontal connection 16 of the T-shaped connecting piece 15, 16 and is conveyed there by the hot flow of air acting in the direction indicated by the arrow A" through the conveying line 18 into the annular channel 19 from which it falls back into the container 10. A regular circulation is thus produced by the continuously acting flow of air. When the desired degree of drying has been reached it is possible by actuating the ball valve 33 to remove part or even all the treatment material G" through the valve tube 32. After the refilling of the filling funnel 10, another drying period can then be carried out.

It is self-evident that the embodiment shown and described is merely to be considered as one practical example for the reduction to practice of the invention and that the invention is by no means intended to be restricted to it. Rather, many other embodiments are possible within the scope of the invention. This is true in particular of the manner and development of the circulation drying on the one hand and the arrangement of the heating device on the other hand. However, it is impor tant that optimum design of the apparatus be effected from the standpoint of heat storage so that a high efficiency can be obtained with the least possible expenditure of energy.

While we have disclosed one embodiment of the present invention, it is to be understood that these embodiments are given by example only and not in a limiting sense.

We claim:

1. An apparatus for treating granular material, such as plastic granulate or the like, developed as a circulation drier acting on the treatment material with high air temperature and brief time of heating in the manner of a heat shock, comprismg a funnel-shaped storage container in which the material treated is contained having an upper filling opening and a lower outlet portion having a lower outlet opening,

a T-member having horizontal disposed branches and a vertical connection branch, said lower outlet portion of said container being operatively connected to said vertical connection branch for discharge of said material from said container,

a pressure air blower,

an air feed line operatively connected with said blower, said air feed line being connected downstream of said air blower to one of said horizontal disposed branches of said T-rnember,

an automatically controlled heater operatively interposed between said blower and said one end of said horizontal disposed branches of said T-member,

a conveyor line connected to the other horizontal disposed branch of said T-member and operatively to said lower outlet portion of said storage container,

an annular channel of approximately U-shape cross section with the opening of the U pointing towards the bottom, constituting an air separator, said annular channel extending concentrically around said upper filling opening in the inside of said storage container,

said conveyor line being operatively connected to said annular channel,

an outlet valve disposed in the center of said lower outlet opening in said storage container and controllable from the outside and extending in a vertical direction downwardly and outwardly through said horizontal disposed branches of said T-member,

an air guide web substantially disposed in a plane in the front portion of said T-member within said T-member, said web effecting an eddy-free flow of dry air, and

a common insulated housing constituting a heat storage device, said storage container, said heater and said air blower being disposed in said housing.

2. The apparatus, as set forth in claim 1, further comprising means for controlling the temperature of the treatment material in said storage container on the one hand and the heating temperature of the air feed in an outlet portion of said heater on the other hand independently of each other.

3. The apparatus, as set forth in claim 1, further comprising a connecting line connected to said blower,

said heater is arranged parallel to and laterally alongside said storage container and includes a top air-flow inlet opening operatively connected with said connecting line, the latter extending laterally in a vertical plane alongside said heater, and

.- an elbow acting as an air cushion connecting said top airflow inlet opening with said connecting line.

4. The apparatus, as set forth in claim 1, wherein said air feed line extends horizontally and is connected to said heater, receiving hot air,

said air guide web is provided within said T-member in a transition region between said lower outlet opening on the storage container side and said air feed line,

said air guide web passes through said T-member transversely to the longitudinal axis both over parts of its height and over parts of its width and defining lateral air passage slots, and

said air guide web having a concave curvature in the direction of flow of the air in the radius of said lower outlet portion on said storage container side and constitutes a bottom extension of said lower outlet portion.

5. The apparatus, as set forth in claim 1, wherein said air feed line runs in a horizontal plane,

said storage container sided lower outlet portion extends over a part of its height into the free cross section of said T-member which constitutes an extension of said air feed line in such a manner that said lower outlet opening of said lower outlet portion lies at approximately the midheight of the cross-sectional height of said air feed line in the region of said T-member.

6. The apparatus, as set forth in claim 1, wherein said outlet valve on said storage container side comprises a ball valve, including a valve ball and an outwardly passing actuating rod,

said valve ball is operatively connected to said actuating rod,

a valve tube concentrically disposed in said lower outlet portion and passing out of said T-member, and

said valve ball cooperates with an open end of said valve tube for opening and closing said valve tube. 

1. An apparatus for treating granular material, such as plastic granulate or the like, developed as a circulation drier acting on the treatment material with high air temperature and brief time of heating in the manner of a heat shock, comprising a funnel-shaped storage container in which the material treated is contained having an upper filling opening and a lower outlet portion having a lower outlet opening, a T-member having horizontal disposed branches and a vertical connection branch, said lower outlet portion of said container being operatively connected to said vertical connection branch for discharge of said material from said container, a pressure air blower, an air feed line operatively connected with said blower, said air feed line being connected downstream of said air blower to one of said horizontal disposed branches of said T-member, an automatically controlled heater operatively interposed between said blower and said one end of said horizontal disposed branches of said T-member, a conveyor line connected to the other horizontal disposed branch of said T-member and operatively to said lower outlet portion of said storage container, an annular channel of approximately U-shape cross section with the opening of the U pointing towards the bottom, constituting an air separator, said annular channel extending concentrically around said upper filling opening in the inside of said storage container, said conveyor line being operatively connected to said annular channel, an outlet valve disposed in the center of said lower outlet opening in said storage container and controllable from the outside and extending in a vertical direction downwardly and outwardly through said horizontal disposed branches of said Tmember, an air guide web substantially disposed in a plane in the front portion of said T-member within said T-member, said web effecting an eddy-free flow of dry air, and a common insulated housing constituting a heat storage device, said storage container, said heater and said air blower being disposed in said housing.
 2. The apparatus, as set forth in claim 1, further comprising means for controlling the temperature of the treatment material in said storage container on the one hand and the heating temperature of the air feed in an outlet portion of said heater on the oTher hand independently of each other.
 3. The apparatus, as set forth in claim 1, further comprising a connecting line connected to said blower, said heater is arranged parallel to and laterally alongside said storage container and includes a top air-flow inlet opening operatively connected with said connecting line, the latter extending laterally in a vertical plane alongside said heater, and an elbow acting as an air cushion connecting said top air-flow inlet opening with said connecting line.
 4. The apparatus, as set forth in claim 1, wherein said air feed line extends horizontally and is connected to said heater, receiving hot air, said air guide web is provided within said T-member in a transition region between said lower outlet opening on the storage container side and said air feed line, said air guide web passes through said T-member transversely to the longitudinal axis both over parts of its height and over parts of its width and defining lateral air passage slots, and said air guide web having a concave curvature in the direction of flow of the air in the radius of said lower outlet portion on said storage container side and constitutes a bottom extension of said lower outlet portion.
 5. The apparatus, as set forth in claim 1, wherein said air feed line runs in a horizontal plane, said storage container sided lower outlet portion extends over a part of its height into the free cross section of said T-member which constitutes an extension of said air feed line in such a manner that said lower outlet opening of said lower outlet portion lies at approximately the mid-height of the cross-sectional height of said air feed line in the region of said T-member.
 6. The apparatus, as set forth in claim 1, wherein said outlet valve on said storage container side comprises a ball valve, including a valve ball and an outwardly passing actuating rod, said valve ball is operatively connected to said actuating rod, a valve tube concentrically disposed in said lower outlet portion and passing out of said T-member, and said valve ball cooperates with an open end of said valve tube for opening and closing said valve tube. 